The strategy for preventing and treating the Pandemic (H1N1) 2009 at Taiwan adopts the western medicine methodology, while that in China focuses on the integrated treatment of the Traditional Chinese Medicine (TCM) with western medicine together. Tamiflu and Relenza, the antiviral drugs against influenza A virus, are both clinically effective in prevention and treatment of seasonal or pandemic influenza. China issued the official TCM clinical recommendations and guidelines for prevention and treatment against H1N1, based on the mechanism of the differentiation of symptoms and signs for classification of syndromes in the TCM system. The mechanism and the clinical usage of the anti-influenza virus drugs are elaborated. The PubMed Database and the Cochrane Database of Systematic Reviews are searched to identify the mechanism and clinical evidence of TCM herbs and prescriptions. Their evidence from western anti-virus, anti-inflammation and immuno-modulation model-based mechanisms is compared with the TCM healing mechanism of the ”exterior syndromes”. A new TCM mouthwash preparation of anti-inflammatory and heat-clearing effect based on western medical evidence and TCM principle is proposed for the prevention of pandemic H1N1 influenza.